We will continue to compare the catalytic properties of glycolytic enzymes in the crystalline and dissolved state, especially hexokinase, pyruvate kinase, and phosphofructokinase. By using highly labeled substrates one can determine the catalytic reaction independent of product release. We will use enolpyruvate as a reagent to determine reaction mechanisms of several important enzymes such as malic enzyme and pyruvate carboxylase. We will study pyruvate kinase also to examine the finding of others that it causes beta-gamma oxygen bridge scrambling of ATP.